freebsd-dev/bin/ps/ps.1
Mateusz Piotrowski f11e51a920 ps(1): Pet mandoc and igor
- Use Xr to reference other manual pages.
- Reference execve(2) instead of exec(2) as exec(2) does not exist.
- Remove the deprecated "Tn" macro.
- Improve the formatting of the etime description.

Reviewed by:	bcr
Approved by:	krion (mentor, implicit), mat (mentor, implicit)
MFC after:	3 days
Differential Revision:	https://reviews.freebsd.org/D17780
2018-10-31 17:47:08 +00:00

801 lines
22 KiB
Groff

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.\" @(#)ps.1 8.3 (Berkeley) 4/18/94
.\" $FreeBSD$
.\"
.Dd October 31, 2018
.Dt PS 1
.Os
.Sh NAME
.Nm ps
.Nd process status
.Sh SYNOPSIS
.Nm
.Op Fl -libxo
.Op Fl aCcdefHhjlmrSTuvwXxZ
.Op Fl O Ar fmt | Fl o Ar fmt
.Op Fl G Ar gid Ns Op , Ns Ar gid Ns Ar ...
.Op Fl J Ar jid Ns Op , Ns Ar jid Ns Ar ...
.Op Fl M Ar core
.Op Fl N Ar system
.Op Fl p Ar pid Ns Op , Ns Ar pid Ns Ar ...
.Op Fl t Ar tty Ns Op , Ns Ar tty Ns Ar ...
.Op Fl U Ar user Ns Op , Ns Ar user Ns Ar ...
.Nm
.Op Fl -libxo
.Op Fl L
.Sh DESCRIPTION
The
.Nm
utility
displays a header line, followed by lines containing information about
all of your
processes that have controlling terminals.
If the
.Fl x
options is specified,
.Nm
will also display processes that do not have controlling terminals.
.Pp
A different set of processes can be selected for display by using any
combination of the
.Fl a , G , J , p , T , t ,
and
.Fl U
options.
If more than one of these options are given, then
.Nm
will select all processes which are matched by at least one of the
given options.
.Pp
For the processes which have been selected for display,
.Nm
will usually display one line per process.
The
.Fl H
option may result in multiple output lines (one line per thread) for
some processes.
By default all of these output lines are sorted first by controlling
terminal, then by process ID.
The
.Fl m , r , u ,
and
.Fl v
options will change the sort order.
If more than one sorting option was given, then the selected processes
will be sorted by the last sorting option which was specified.
.Pp
For the processes which have been selected for display, the information
to display is selected based on a set of keywords (see the
.Fl L , O ,
and
.Fl o
options).
The default output format includes, for each process, the process' ID,
controlling terminal, state, CPU time (including both user and system time)
and associated command.
.Pp
If the
.Nm
process is associated with a terminal, the default output width is that of the
terminal; otherwise the output width is unlimited.
See also the
.Fl w
option.
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl -libxo
Generate output via
.Xr libxo 3
in a selection of different human and machine readable formats.
See
.Xr xo_parse_args 3
for details on command line arguments.
.It Fl a
Display information about other users' processes as well as your own.
If the
.Va security.bsd.see_other_uids
sysctl is set to zero, this option is honored only if the UID of the user is 0.
.It Fl c
Change the
.Dq command
column output to just contain the executable name,
rather than the full command line.
.It Fl C
Change the way the CPU percentage is calculated by using a
.Dq raw
CPU calculation that ignores
.Dq resident
time (this normally has
no effect).
.It Fl d
Arrange processes into descendancy order and prefix each command with
indentation text showing sibling and parent/child relationships as a tree.
If either of the
.Fl m
and
.Fl r
options are also used, they control how sibling processes are sorted
relative to each other.
Note that this option has no effect if the
.Dq command
column is not the last column displayed.
.It Fl e
Display the environment as well.
.It Fl f
Show command-line and environment information about swapped out processes.
This option is honored only if the UID of the user is 0.
.It Fl G
Display information about processes which are running with the specified
real group IDs.
.It Fl H
Show all of the threads associated with each process.
.It Fl h
Repeat the information header as often as necessary to guarantee one
header per page of information.
.It Fl j
Print information associated with the following keywords:
.Cm user , pid , ppid , pgid , sid , jobc , state , tt , time ,
and
.Cm command .
.It Fl J
Display information about processes which match the specified jail IDs.
This may be either the
.Cm jid
or
.Cm name
of the jail.
Use
.Fl J
.Sy 0
to display only host processes.
This flag implies
.Fl x
by default.
.It Fl L
List the set of keywords available for the
.Fl O
and
.Fl o
options.
.It Fl l
Display information associated with the following keywords:
.Cm uid , pid , ppid , cpu , pri , nice , vsz , rss , mwchan , state ,
.Cm tt , time ,
and
.Cm command .
.It Fl M
Extract values associated with the name list from the specified core
instead of the currently running system.
.It Fl m
Sort by memory usage, instead of the combination of controlling
terminal and process ID.
.It Fl N
Extract the name list from the specified system instead of the default,
which is the kernel image the system has booted from.
.It Fl O
Add the information associated with the space or comma separated list
of keywords specified, after the process ID,
in the default information
display.
Keywords may be appended with an equals
.Pq Ql =
sign and a string.
This causes the printed header to use the specified string instead of
the standard header.
.It Fl o
Display information associated with the space or comma separated
list of keywords specified.
The last keyword in the list may be appended with an equals
.Pq Ql =
sign and a string that spans the rest of the argument, and can contain
space and comma characters.
This causes the printed header to use the specified string instead of
the standard header.
Multiple keywords may also be given in the form of more than one
.Fl o
option.
So the header texts for multiple keywords can be changed.
If all keywords have empty header texts, no header line is written.
.It Fl p
Display information about processes which match the specified process IDs.
.It Fl r
Sort by current CPU usage, instead of the combination of controlling
terminal and process ID.
.It Fl S
Change the way the process times, namely cputime, systime, and usertime,
are calculated by summing all exited children to their parent process.
.It Fl T
Display information about processes attached to the device associated
with the standard input.
.It Fl t
Display information about processes attached to the specified terminal
devices.
Full pathnames, as well as abbreviations (see explanation of the
.Cm tt
keyword) can be specified.
.It Fl U
Display the processes belonging to the specified usernames.
.It Fl u
Display information associated with the following keywords:
.Cm user , pid , %cpu , %mem , vsz , rss , tt , state , start , time ,
and
.Cm command .
The
.Fl u
option implies the
.Fl r
option.
.It Fl v
Display information associated with the following keywords:
.Cm pid , state , time , sl , re , pagein , vsz , rss , lim , tsiz ,
.Cm %cpu , %mem ,
and
.Cm command .
The
.Fl v
option implies the
.Fl m
option.
.It Fl w
Use at least 132 columns to display information, instead of the default which
is the window size if
.Nm
is associated with a terminal.
If the
.Fl w
option is specified more than once,
.Nm
will use as many columns as necessary without regard for the window size.
Note that this option has no effect if the
.Dq command
column is not the last column displayed.
.It Fl X
When displaying processes matched by other options, skip any processes
which do not have a controlling terminal.
This is the default behaviour.
.It Fl x
When displaying processes matched by other options, include processes
which do not have a controlling terminal.
This is the opposite of the
.Fl X
option.
If both
.Fl X
and
.Fl x
are specified in the same command, then
.Nm
will use the one which was specified last.
.It Fl Z
Add
.Xr mac 4
label to the list of keywords for which
.Nm
will display information.
.El
.Pp
A complete list of the available keywords are listed below.
Some of these keywords are further specified as follows:
.Bl -tag -width lockname
.It Cm %cpu
The CPU utilization of the process; this is a decaying average over up to
a minute of previous (real) time.
Since the time base over which this is computed varies (since processes may
be very young) it is possible for the sum of all
.Cm %cpu
fields to exceed 100%.
.It Cm %mem
The percentage of real memory used by this process.
.It Cm class
Login class associated with the process.
.It Cm flags
The flags associated with the process as in
the include file
.In sys/proc.h :
.Bl -column P_SINGLE_BOUNDARY 0x40000000
.It Dv "P_ADVLOCK" Ta No "0x00001" Ta "Process may hold a POSIX advisory lock"
.It Dv "P_CONTROLT" Ta No "0x00002" Ta "Has a controlling terminal"
.It Dv "P_KPROC" Ta No "0x00004" Ta "Kernel process"
.It Dv "P_PPWAIT" Ta No "0x00010" Ta "Parent is waiting for child to exec/exit"
.It Dv "P_PROFIL" Ta No "0x00020" Ta "Has started profiling"
.It Dv "P_STOPPROF" Ta No "0x00040" Ta "Has thread in requesting to stop prof"
.It Dv "P_HADTHREADS" Ta No "0x00080" Ta "Has had threads (no cleanup shortcuts)"
.It Dv "P_SUGID" Ta No "0x00100" Ta "Had set id privileges since last exec"
.It Dv "P_SYSTEM" Ta No "0x00200" Ta "System proc: no sigs, stats or swapping"
.It Dv "P_SINGLE_EXIT" Ta No "0x00400" Ta "Threads suspending should exit, not wait"
.It Dv "P_TRACED" Ta No "0x00800" Ta "Debugged process being traced"
.It Dv "P_WAITED" Ta No "0x01000" Ta "Someone is waiting for us"
.It Dv "P_WEXIT" Ta No "0x02000" Ta "Working on exiting"
.It Dv "P_EXEC" Ta No "0x04000" Ta "Process called exec"
.It Dv "P_WKILLED" Ta No "0x08000" Ta "Killed, shall go to kernel/user boundary ASAP"
.It Dv "P_CONTINUED" Ta No "0x10000" Ta "Proc has continued from a stopped state"
.It Dv "P_STOPPED_SIG" Ta No "0x20000" Ta "Stopped due to SIGSTOP/SIGTSTP"
.It Dv "P_STOPPED_TRACE" Ta No "0x40000" Ta "Stopped because of tracing"
.It Dv "P_STOPPED_SINGLE" Ta No "0x80000" Ta "Only one thread can continue"
.It Dv "P_PROTECTED" Ta No "0x100000" Ta "Do not kill on memory overcommit"
.It Dv "P_SIGEVENT" Ta No "0x200000" Ta "Process pending signals changed"
.It Dv "P_SINGLE_BOUNDARY" Ta No "0x400000" Ta "Threads should suspend at user boundary"
.It Dv "P_HWPMC" Ta No "0x800000" Ta "Process is using HWPMCs"
.It Dv "P_JAILED" Ta No "0x1000000" Ta "Process is in jail"
.It Dv "P_TOTAL_STOP" Ta No "0x2000000" Ta "Stopped for system suspend"
.It Dv "P_INEXEC" Ta No "0x4000000" Ta Process is in Xr execve 2
.It Dv "P_STATCHILD" Ta No "0x8000000" Ta "Child process stopped or exited"
.It Dv "P_INMEM" Ta No "0x10000000" Ta "Loaded into memory"
.It Dv "P_SWAPPINGOUT" Ta No "0x20000000" Ta "Process is being swapped out"
.It Dv "P_SWAPPINGIN" Ta No "0x40000000" Ta "Process is being swapped in"
.It Dv "P_PPTRACE" Ta No "0x80000000" Ta "Vforked child issued ptrace(PT_TRACEME)"
.El
.It Cm flags2
The flags kept in
.Va p_flag2
associated with the process as in
the include file
.In sys/proc.h :
.Bl -column P2_INHERIT_PROTECTED 0x00000001
.It Dv "P2_INHERIT_PROTECTED" Ta No "0x00000001" Ta "New children get P_PROTECTED"
.It Dv "P2_NOTRACE" Ta No "0x00000002" Ta "No" Xr ptrace 2 attach or coredumps
.It Dv "P2_NOTRACE_EXEC" Ta No "0x00000004" Ta Keep P2_NOPTRACE on Xr execve 2
.It Dv "P2_AST_SU" Ta No "0x00000008" Ta "Handles SU ast for kthreads"
.It Dv "P2_PTRACE_FSTP" Ta No "0x00000010" Ta "SIGSTOP from PT_ATTACH not yet handled"
.El
.It Cm label
The MAC label of the process.
.It Cm lim
The soft limit on memory used, specified via a call to
.Xr setrlimit 2 .
.It Cm lstart
The exact time the command started, using the
.Ql %c
format described in
.Xr strftime 3 .
.It Cm lockname
The name of the lock that the process is currently blocked on.
If the name is invalid or unknown, then
.Dq ???\&
is displayed.
.It Cm logname
The login name associated with the session the process is in (see
.Xr getlogin 2 ) .
.It Cm mwchan
The event name if the process is blocked normally, or the lock name if
the process is blocked on a lock.
See the wchan and lockname keywords
for details.
.It Cm nice
The process scheduling increment (see
.Xr setpriority 2 ) .
.It Cm rss
the real memory (resident set) size of the process (in 1024 byte units).
.It Cm start
The time the command started.
If the command started less than 24 hours ago, the start time is
displayed using the
.Dq Li %H:%M
format described in
.Xr strftime 3 .
If the command started less than 7 days ago, the start time is
displayed using the
.Dq Li %a%H
format.
Otherwise, the start time is displayed using the
.Dq Li %e%b%y
format.
.It Cm state
The state is given by a sequence of characters, for example,
.Dq Li RWNA .
The first character indicates the run state of the process:
.Pp
.Bl -tag -width indent -compact
.It Li D
Marks a process in disk (or other short term, uninterruptible) wait.
.It Li I
Marks a process that is idle (sleeping for longer than about 20 seconds).
.It Li L
Marks a process that is waiting to acquire a lock.
.It Li R
Marks a runnable process.
.It Li S
Marks a process that is sleeping for less than about 20 seconds.
.It Li T
Marks a stopped process.
.It Li W
Marks an idle interrupt thread.
.It Li Z
Marks a dead process (a
.Dq zombie ) .
.El
.Pp
Additional characters after these, if any, indicate additional state
information:
.Pp
.Bl -tag -width indent -compact
.It Li +
The process is in the foreground process group of its control terminal.
.It Li <
The process has raised CPU scheduling priority.
.It Li C
The process is in
.Xr capsicum 4
capability mode.
.It Li E
The process is trying to exit.
.It Li J
Marks a process which is in
.Xr jail 2 .
The hostname of the prison can be found in
.Pa /proc/ Ns Ao Ar pid Ac Ns Pa /status .
.It Li L
The process has pages locked in core (for example, for raw I/O).
.It Li N
The process has reduced CPU scheduling priority (see
.Xr setpriority 2 ) .
.It Li s
The process is a session leader.
.It Li V
The process' parent is suspended during a
.Xr vfork 2 ,
waiting for the process to exec or exit.
.It Li W
The process is swapped out.
.It Li X
The process is being traced or debugged.
.El
.It Cm tt
An abbreviation for the pathname of the controlling terminal, if any.
The abbreviation consists of the three letters following
.Pa /dev/tty ,
or, for pseudo-terminals, the corresponding entry in
.Pa /dev/pts .
This is followed by a
.Ql -
if the process can no longer reach that
controlling terminal (i.e., it has been revoked).
A
.Ql -
without a preceding two letter abbreviation or pseudo-terminal device number
indicates a process which never had a controlling terminal.
The full pathname of the controlling terminal is available via the
.Cm tty
keyword.
.It Cm wchan
The event (an address in the system) on which a process waits.
When printed numerically, the initial part of the address is
trimmed off and the result is printed in hex, for example, 0x80324000 prints
as 324000.
.El
.Pp
When printing using the command keyword, a process that has exited and
has a parent that has not yet waited for the process (in other words, a zombie)
is listed as
.Dq Li <defunct> ,
and a process which is blocked while trying
to exit is listed as
.Dq Li <exiting> .
If the arguments cannot be located (usually because it has not been set, as is
the case of system processes and/or kernel threads) the command name is printed
within square brackets.
The
.Nm
utility first tries to obtain the arguments cached by the kernel (if they were
shorter than the value of the
.Va kern.ps_arg_cache_limit
sysctl).
The process can change the arguments shown with
.Xr setproctitle 3 .
Otherwise,
.Nm
makes an educated guess as to the file name and arguments given when the
process was created by examining memory or the swap area.
The method is inherently somewhat unreliable and in any event a process
is entitled to destroy this information.
The ucomm (accounting) keyword can, however, be depended on.
If the arguments are unavailable or do not agree with the ucomm keyword,
the value for the ucomm keyword is appended to the arguments in parentheses.
.Sh KEYWORDS
The following is a complete list of the available keywords and their
meanings.
Several of them have aliases (keywords which are synonyms).
.Pp
.Bl -tag -width ".Cm sigignore" -compact
.It Cm %cpu
percentage CPU usage (alias
.Cm pcpu )
.It Cm %mem
percentage memory usage (alias
.Cm pmem )
.It Cm acflag
accounting flag (alias
.Cm acflg )
.It Cm args
command and arguments
.It Cm class
login class
.It Cm comm
command
.It Cm command
command and arguments
.It Cm cow
number of copy-on-write faults
.It Cm cpu
short-term CPU usage factor (for scheduling)
.It Cm dsiz
data size (in Kbytes)
.It Cm emul
system-call emulation environment (ABI)
.It Cm etime
elapsed running time, format
.Do
.Op days- Ns
.Op hours\&: Ns
minutes:seconds
.Dc
.It Cm etimes
elapsed running time, in decimal integer seconds
.It Cm fib
default FIB number, see
.Xr setfib 1
.It Cm flags
the process flags, in hexadecimal (alias
.Cm f )
.It Cm flags2
the additional set of process flags, in hexadecimal (alias
.Cm f2 )
.It Cm gid
effective group ID (alias
.Cm egid )
.It Cm group
group name (from egid) (alias
.Cm egroup )
.It Cm inblk
total blocks read (alias
.Cm inblock )
.It Cm jail
jail name
.It Cm jid
jail ID
.It Cm jobc
job control count
.It Cm ktrace
tracing flags
.It Cm label
MAC label
.It Cm lim
memoryuse limit
.It Cm lockname
lock currently blocked on (as a symbolic name)
.It Cm logname
login name of user who started the session
.It Cm lstart
time started
.It Cm lwp
thread (light-weight process) ID (alias
.Cm tid )
.It Cm majflt
total page faults
.It Cm minflt
total page reclaims
.It Cm msgrcv
total messages received (reads from pipes/sockets)
.It Cm msgsnd
total messages sent (writes on pipes/sockets)
.It Cm mwchan
wait channel or lock currently blocked on
.It Cm nice
nice value (alias
.Cm ni )
.It Cm nivcsw
total involuntary context switches
.It Cm nlwp
number of threads (light-weight processes) tied to a process
.It Cm nsigs
total signals taken (alias
.Cm nsignals )
.It Cm nswap
total swaps in/out
.It Cm nvcsw
total voluntary context switches
.It Cm nwchan
wait channel (as an address)
.It Cm oublk
total blocks written (alias
.Cm oublock )
.It Cm paddr
process pointer
.It Cm pagein
pageins (same as majflt)
.It Cm pgid
process group number
.It Cm pid
process ID
.It Cm ppid
parent process ID
.It Cm pri
scheduling priority
.It Cm re
core residency time (in seconds; 127 = infinity)
.It Cm rgid
real group ID
.It Cm rgroup
group name (from rgid)
.It Cm rss
resident set size
.It Cm rtprio
realtime priority (101 = not a realtime process)
.It Cm ruid
real user ID
.It Cm ruser
user name (from ruid)
.It Cm sid
session ID
.It Cm sig
pending signals (alias
.Cm pending )
.It Cm sigcatch
caught signals (alias
.Cm caught )
.It Cm sigignore
ignored signals (alias
.Cm ignored )
.It Cm sigmask
blocked signals (alias
.Cm blocked )
.It Cm sl
sleep time (in seconds; 127 = infinity)
.It Cm ssiz
stack size (in Kbytes)
.It Cm start
time started
.It Cm state
symbolic process state (alias
.Cm stat )
.It Cm svgid
saved gid from a setgid executable
.It Cm svuid
saved UID from a setuid executable
.It Cm systime
accumulated system CPU time
.It Cm tdaddr
thread address
.It Cm tdname
thread name
.It Cm tdev
control terminal device number
.It Cm time
accumulated CPU time, user + system (alias
.Cm cputime )
.It Cm tpgid
control terminal process group ID
.It Cm tracer
tracer process ID
.\".It Cm trss
.\"text resident set size (in Kbytes)
.It Cm tsid
control terminal session ID
.It Cm tsiz
text size (in Kbytes)
.It Cm tt
control terminal name (two letter abbreviation)
.It Cm tty
full name of control terminal
.It Cm ucomm
name to be used for accounting
.It Cm uid
effective user ID (alias
.Cm euid )
.It Cm upr
scheduling priority on return from system call (alias
.Cm usrpri )
.It Cm uprocp
process pointer
.It Cm user
user name (from UID)
.It Cm usertime
accumulated user CPU time
.It Cm vmaddr
vmspace pointer
.It Cm vsz
virtual size in Kbytes (alias
.Cm vsize )
.It Cm wchan
wait channel (as a symbolic name)
.It Cm xstat
exit or stop status (valid only for stopped or zombie process)
.El
.Pp
Note that the
.Cm pending
column displays bitmask of signals pending in the process queue when
.Fl H
option is not specified, otherwise the per-thread queue of pending signals
is shown.
.Sh ENVIRONMENT
The following environment variables affect the execution of
.Nm :
.Bl -tag -width ".Ev COLUMNS"
.It Ev COLUMNS
If set, specifies the user's preferred output width in column positions.
By default,
.Nm
attempts to automatically determine the terminal width.
.El
.Sh FILES
.Bl -tag -width ".Pa /boot/kernel/kernel" -compact
.It Pa /boot/kernel/kernel
default system namelist
.El
.Sh EXIT STATUS
.Ex -std
.Sh EXAMPLES
Display information on all system processes:
.Pp
.Dl $ ps -auxw
.Sh SEE ALSO
.Xr kill 1 ,
.Xr pgrep 1 ,
.Xr pkill 1 ,
.Xr procstat 1 ,
.Xr w 1 ,
.Xr kvm 3 ,
.Xr libxo 3 ,
.Xr strftime 3 ,
.Xr xo_parse_args 3 ,
.Xr mac 4 ,
.Xr procfs 5 ,
.Xr pstat 8 ,
.Xr sysctl 8 ,
.Xr mutex 9
.Sh STANDARDS
For historical reasons, the
.Nm
utility under
.Fx
supports a different set of options from what is described by
.St -p1003.2 ,
and what is supported on
.No non- Ns Bx
operating systems.
.Sh HISTORY
The
.Nm
command appeared in
.At v3
in section 8 of the manual.
.Sh BUGS
Since
.Nm
cannot run faster than the system and is run as any other scheduled
process, the information it displays can never be exact.
.Pp
The
.Nm
utility does not correctly display argument lists containing multibyte
characters.